Comment 7 for bug 683211

The workaround (revert back) until this regression of the compiz functionallity is fixed is to remove the desktop wall dependency in the file /usr/share/compiz/unityshell.xml, i.e remove the line <plugin>wall</plugin> in the <requirement> clause on line 35 followed by a relogin.

Personally, I think this bug should be reset until a more solid solution is found.